Pipe ramming is a widely used method for installing underground metal pipes especially in large sizes such as 2+ feet in diameter. In one such process, a pneumatic impact tool engages one end opening of the pipeline and forces it through the ground either horizontally or on a vertical grade that departs from horizontal. Wentworth U.S. Pat. No. 5,505,270, Apr. 9, 1996, exemplifies a pneumatic impact tool preferred for use in pipe ramming of large diameter iron and steel pipes and is incorporated by reference herein. Pipe lengths of up to 40 feet are rammed into the ground after which a further pipe section is welded to the exposed end of the installed pipe, and the ramming tool is then relocated to the exposed end of the new pipe section, after which ramming is resumed. To move the impact tool and pipe sections, the arm of an excavator is typically used to raise and lower components into place.
In the event a vertical grade is to be maintained, current practice uses boards or beams inserted underneath the pipe section being rammed, with wedges hammered into place by hand in order to angle the pipe section as needed. This is a difficult and laborious process and is limited in the scope of changes in vertical grade (up/down) and horizontal grade (left/right) that can be made. The present invention seeks to improve on this procedure.